<template>
    <div>
        <router-link tag="div" to="/" class="header-abs" v-show="showAbs">
            <div class="iconfont header-abs-back">&#xe600;</div>
        </router-link>
     <div class="header-fixed" v-show="!showAbs" :style="opacityStyle">
         <router-link to="/">
            <div class="iconfont header-fixed-back">&#xe600;</div>
        </router-link>
       景点详情
        </div>
    </div>

</template>

<script>
export default {
  name: 'DetailHeader',
  data () {
    return {
      showAbs: true,
      opacityStyle: {
        opacity: 0
      }
    }
  },
  methods: {
    handleScroll () {
      const top = document.documentElement.scrollTop
      if (top > 60) {
        let opacity = top / 140
        opacity = opacity > 1 ? 1 : opacity
        this.opacityStyle = {opacity}
        this.showAbs = false
      } else {
        this.showAbs = true
      }
    }
  },
  activated () {
    window.addEventListener('scroll', this.handleScroll)
  },
  deactivated () {
    window.removeEventListener('scroll', this.handleScroll)
  }
}
</script>

<style lang="stylus" scoped>
@import '~styles/varibles.styl'
  .header-abs
    position :absolute
    top:.2rem
    left :.2rem
    width :.8rem
    height :.8rem
    background :rgba(0,0,0,.8)
    border-radius:.4rem
    text-align :center
    line-height :.8rem
    .header-abs-back
     color:#fff
     font-size:.4rem
  .header-fixed
    position :fixed
    top:0
    left: 0
    right :0
    height:.86rem
    line-height:.86rem
    text-align :center
    color:#fff
    background:$bgColor
    font-size:.32rem
    z-index:99
    .header-fixed-back
      position:absolute
      color :#fff
      top:0
      left :0
      width :.64rem
      font-size :.32rem
</style>
